1. Field of the Invention
The present invention relates generally to a structure for a tripod constant velocity joint and a method of assembling a roller assembly and, more particularly, to a structure for a tripod constant velocity joint and a method of assembling a roller assembly, which maintain the structural stability of the tripod constant velocity joint, and minimize the frictional force between a trunnion and a track, thus remarkably reducing the generation of axial force, therefore ensuring the stable operation and durability of the constant velocity joint.
2. Description of the Related Art
Generally, a tripod constant joint is constructed to transmit power, using a housing, which is integrally coupled to a stub shaft, and a spider, which is inserted into the housing and spline-coupled to a half shaft. Three trunnions are provided on the spider. Each of the trunnions is provided with rollers and bearings so as to absorb relative motion which occurs between the trunnion and the track of the housing. When the stub shaft and the half shaft of the tripod constant velocity joint are bent, relative motion occurs between the trunnions, the rollers, the bearings, and the track. The frictional force generated by the relative motion generates an axial force in the axial direction of the half shaft. The axial force attains its maximum value three times during one rotation of the tripod constant velocity joint.
Such an axial force is further increased when the load acting on the constant velocity joint is large, as in the sudden acceleration of a vehicle, or when a joint angle is large. Further, the axial force is problematic in that it causes horizontal vibration of the vehicle.